Magnetotelluric data were recorded at the University of Victoria for a wide period range since the summer of 1968. Data for periods between 10 s and 104 s were used for interpretation. Telluric signals were found to be strongly anisotropic for the entire frequency range. Several possible causes of this anisotropy including the land–sea interface and a geological fault at Victoria are discussed.In order to obtain a 'model' for the subsurface conductivity structure, the apparent resistivity curves for both electric field components (E parallel and E perpendicular to the direction of polarization) are combined into one interpretation. The model proposes a thin, highly conducting layer near the surface of a highly resistive earth.The validity of the rotation used in transforming anisotropic telluric data before interpretation was tested experimentally.

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